NASA's Phoenix Mission Faces Survival Challenges

In a race against time and the elements, engineers with NASA's Phoenix Mars Lander mission hope to extend the lander's survival by gradually shutting down some of its instruments and heaters.

Originally scheduled to last 90 days, Phoenix has completed a fifth month of exploration in the Martian arctic. As expected, with the Martian northern hemisphere shifting from summer to fall, the lander is generating less power due to shorter days and fewer hours of sunlight reaching its solar panels. At the same time, the spacecraft requires more power to run several survival heaters that allow it to operate even as temperatures decline.

Over the next several weeks, four survival heaters will be shut down, one at a time, in an effort to conserve power. The heaters serve the purpose of keeping the electronics within tested survivable limits. As each heater is disabled, some of the instruments are also expected to cease operations. The energy saved is intended to power the lander's main camera and meteorological instruments until the very end of the mission.

This would leave one remaining survival heater to run out on its own.

"At that point, Phoenix will be at the mercy of Mars," said Chris Lewicki of JPL, lead mission manger.

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